Fuel pumps are used to deliver fuel from a fuel tank to an internal combustion engine of a vehicle. Most fuel pumps are mounted in the fuel tanks of the vehicle and therefore are made to operate over a wide range of ambient temperatures.
Generally, a vehicle fuel pump is driven by an electric motor and they are both mounted inside a housing. The pump is coupled to the armature of the electric motor and draws fuel through an inlet port and discharges the fuel through an outlet port. The pump and electric motor generate heat within the housing and are cooled by the liquid fuel flowing through the pump housing. During use, the vehicle may continue to operate for a period of time even though there is no liquid fuel flow through the fuel pump. For instance, when the fuel tank becomes empty the fuel pump may continue to operate with only fuel vapor in the housing. Without the cooling effect of the liquid fuel flow, the heat generated by the pump and electric motor within the housing can cause the electric motor to overheat and thereby damage or destroy the electric motor.